StudyBrixFree worksheets, study guides and courses

Grade 12 · Biology

Grade 12 Biology diagnostic

15 questions on cells & microscopy, human biology & physiology, genetics & inheritance, ecology & populations and measurement & evidence, plus 3 from Grade 11. Answer what you can, then check your answers to see which topics are secure and what to practise next.

15 questions5 topicsAbout 15 minutesSet 3 of 5

Skip a question if you do not know the answer. It is better than guessing, because it shows what to practise.

1Cells & microscopyWhich structure is found in plant cells but not in animal cells: the chloroplast or the mitochondrion?
2Cells & microscopyWhat separates during mitotic anaphase?
3Human biology & physiologyA fictional circulation model has 100 beats/min and 68 mL/beat. Find its flow in mL/min. These are supplied model values, not diagnostic ranges. Round to 3 decimal places if needed. Answer in mL/min.
mL/min
4Human biology & physiologyDoes homeostasis mean every internal value is exactly constant?
5Genetics & inheritanceIn the simple Aa × Aa inheritance model with independent outcomes, the probability of aa is 1/4. Among 292 offspring, find the expected aa count, not a guaranteed outcome. Round to 3 decimal places if needed.
6Genetics & inheritanceIn pea plants, the allele for round seeds (R) is dominant over the allele for wrinkled seeds (r). Two plants, Rr × Rr, are crossed. What percentage of the offspring are expected to have the genotype RR?
%
7Genetics & inheritanceWhich structure carries out translation?
8Ecology & populationsIn this simplified food chain: oak trees → caterpillar → songbird → hawk. At which trophic level is “oak trees”? (Producers are level 1.)
9Ecology & populationsSupplied fictional records give M = 89 initially marked, C = 58 in a later sample, and R = 12 marked in that sample. Use N ≈ MC/R under the stated assumptions. No animals are to be handled. Round to 3 decimal places if needed.
10Ecology & populationsA fictional population starts at 634. During one interval: 56 births, 33 arrivals, 35 deaths and 37 departures. Find the final count. Round to 3 decimal places if needed.
11Measurement & evidenceInvestigation: Radish seeds are placed on paper towels soaked in water with different salt concentrations, 20 seeds per dish, and the percentage that germinate is recorded. In this investigation, which is a controlled variable?
12Measurement & evidenceDo ten readings of one plant equal ten independently grown plants?

From Grade 11

These questions check skills from the grade below, so gaps can be spotted early.

13Evolution & biodiversity (Grade 11)Which is one dimension of biodiversity?
14Human biology & physiology (Grade 11)What defines a vein?
15Genetics & inheritance (Grade 11)Which describes antiparallel strands?